Laser drivers are used to drive laser diodes within various types of information recording/reproducing apparatuses, such as DVD and CD drives, DVD camcorders, and DVD video recorders. Typically, a laser driver provides a current to a laser diode, causing the laser diode to output a light signal that is incident on an a optical media disk. The magnitude of the current provided by the laser driver (which controls the output power of the laser diode) may vary depending on whether the laser diode is being used to read data from or write data to the media. Further, the magnitude of the current may also depend on specific disc media, DVD or CD standards, and/or the speed at which data is being read or written.
Laser drivers are carefully calibrated so that the power or intensity of the light signal (produced by the laser diode) can be accurately controlled. Nevertheless, environmental variations (such as temperature variations) and aging of the laser diode may affect the characteristics (e.g., slope efficiency) of the laser diode. Accordingly, there is a need to accurately control the power or output of a laser diode to compensate for changes in the laser diode's characteristics. Embodiments of the present invention provides improved methods and systems for controlling the power of a laser diode.